1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
|
/*
* Copyright 2004-2009 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#ifndef __BLACKFIN_MMU_CONTEXT_H__
#define __BLACKFIN_MMU_CONTEXT_H__
#include <linux/gfp.h>
#include <linux/sched.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/cplbinit.h>
#include <asm/sections.h>
/* Note: L1 stacks are CPU-private things, so we bluntly disable this
feature in SMP mode, and use the per-CPU scratch SRAM bank only to
store the PDA instead. */
extern void *current_l1_stack_save;
extern int nr_l1stack_tasks;
extern void *l1_stack_base;
extern unsigned long l1_stack_len;
extern int l1sram_free(const void*);
extern void *l1sram_alloc_max(void*);
static inline void free_l1stack(void)
{
nr_l1stack_tasks--;
if (nr_l1stack_tasks == 0)
l1sram_free(l1_stack_base);
}
static inline unsigned long
alloc_l1stack(unsigned long length, unsigned long *stack_base)
{
if (nr_l1stack_tasks == 0) {
l1_stack_base = l1sram_alloc_max(&l1_stack_len);
if (!l1_stack_base)
return 0;
}
if (l1_stack_len < length) {
if (nr_l1stack_tasks == 0)
l1sram_free(l1_stack_base);
return 0;
}
*stack_base = (unsigned long)l1_stack_base;
nr_l1stack_tasks++;
return l1_stack_len;
}
static inline int
activate_l1stack(struct mm_struct *mm, unsigned long sp_base)
{
if (current_l1_stack_save)
memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
mm->context.l1_stack_save = current_l1_stack_save = (void*)sp_base;
memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
return 1;
}
#define deactivate_mm(tsk,mm) do { } while (0)
#define activate_mm(prev, next) switch_mm(prev, next, NULL)
static inline void __switch_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm,
struct task_struct *tsk)
{
#ifdef CONFIG_MPU
unsigned int cpu = smp_processor_id();
#endif
if (prev_mm == next_mm)
return;
#ifdef CONFIG_MPU
if (prev_mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
flush_switched_cplbs(cpu);
set_mask_dcplbs(next_mm->context.page_rwx_mask, cpu);
}
#endif
#ifdef CONFIG_APP_STACK_L1
/* L1 stack switching. */
if (!next_mm->context.l1_stack_save)
return;
if (next_mm->context.l1_stack_save == current_l1_stack_save)
return;
if (current_l1_stack_save) {
memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
}
current_l1_stack_save = next_mm->context.l1_stack_save;
memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
#endif
}
#ifdef CONFIG_IPIPE
#define lock_mm_switch(flags) local_irq_save_hw_cond(flags)
#define unlock_mm_switch(flags) local_irq_restore_hw_cond(flags)
#else
#define lock_mm_switch(flags) do { (void)(flags); } while (0)
#define unlock_mm_switch(flags) do { (void)(flags); } while (0)
#endif /* CONFIG_IPIPE */
#ifdef CONFIG_MPU
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
unsigned long flags;
lock_mm_switch(flags);
__switch_mm(prev, next, tsk);
unlock_mm_switch(flags);
}
static inline void protect_page(struct mm_struct *mm, unsigned long addr,
unsigned long flags)
{
unsigned long *mask = mm->context.page_rwx_mask;
unsigned long page;
unsigned long idx;
unsigned long bit;
if (unlikely(addr >= ASYNC_BANK0_BASE && addr < ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE))
page = (addr - (ASYNC_BANK0_BASE - _ramend)) >> 12;
else
page = addr >> 12;
idx = page >> 5;
bit = 1 << (page & 31);
if (flags & VM_READ)
mask[idx] |= bit;
else
mask[idx] &= ~bit;
mask += page_mask_nelts;
if (flags & VM_WRITE)
mask[idx] |= bit;
else
mask[idx] &= ~bit;
mask += page_mask_nelts;
if (flags & VM_EXEC)
mask[idx] |= bit;
else
mask[idx] &= ~bit;
}
static inline void update_protections(struct mm_struct *mm)
{
unsigned int cpu = smp_processor_id();
if (mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
flush_switched_cplbs(cpu);
set_mask_dcplbs(mm->context.page_rwx_mask, cpu);
}
}
#else /* !CONFIG_MPU */
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
__switch_mm(prev, next, tsk);
}
#endif
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
}
/* Called when creating a new context during fork() or execve(). */
static inline int
init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
#ifdef CONFIG_MPU
unsigned long p = __get_free_pages(GFP_KERNEL, page_mask_order);
mm->context.page_rwx_mask = (unsigned long *)p;
memset(mm->context.page_rwx_mask, 0,
page_mask_nelts * 3 * sizeof(long));
#endif
return 0;
}
static inline void destroy_context(struct mm_struct *mm)
{
struct sram_list_struct *tmp;
#ifdef CONFIG_MPU
unsigned int cpu = smp_processor_id();
#endif
#ifdef CONFIG_APP_STACK_L1
if (current_l1_stack_save == mm->context.l1_stack_save)
current_l1_stack_save = 0;
if (mm->context.l1_stack_save)
free_l1stack();
#endif
while ((tmp = mm->context.sram_list)) {
mm->context.sram_list = tmp->next;
sram_free(tmp->addr);
kfree(tmp);
}
#ifdef CONFIG_MPU
if (current_rwx_mask[cpu] == mm->context.page_rwx_mask)
current_rwx_mask[cpu] = NULL;
free_pages((unsigned long)mm->context.page_rwx_mask, page_mask_order);
#endif
}
#define ipipe_mm_switch_protect(flags) \
local_irq_save_hw_cond(flags)
#define ipipe_mm_switch_unprotect(flags) \
local_irq_restore_hw_cond(flags)
#endif
|
